Flask-positioning device for pattern plates



June 16, 1925.

H. T. DUDLEY FLASK POSITIONING DEVICE FOR PATTERN PLATES Fileq Jan. 11, 1924 p m I F T TES PATENT HOWARD T. DUDLEY, OF S AGINAVI, MICHIGAN:

I V FL ASK-POSITTONINGDEVICE FOR PATTERN'PLATES.

Application filed January 11, 1924. Serial No. 685,569.

T 0 all whom iii-"may concern:

- Be 1U known that I, HOWARD T. DUDLEY,

a citizen of the United States, residing at Saginaw, in the county of Saginaw and State of Mlchlgan, have invented certain new and useful Improvements in Flask- .Positioning Devices rorPatternvPlates; and

I. do hereby declare the following to 'be' a full", clear, and exact description of the invention, such as Wll'l enable others skilled 111 the art to which it appertams to make and use the same.

This invention is an improvement in molding flasks such as are usually employed in conjunction with moldingmachines.

The particular object of my invention is to provide an improved means for centering the flask members on the pattern plates of a molding machine and for assembling them as a complete mold without springing, bending or twisting, even though the drag orcope orboth may have been sprung or squeezed out of its original rectangular sha peby pressure or blows on its sides or corners.

Flask members,"v1z, drags or copes made at sheet metal or malleable iron are subjected to strains from numerous causes, as by ramming the sand, strains caused by the molten metal, distortion produced by shaking out the castings and by handling and: by piling the flasks. For good moldingevery flask member, even though it be somewhat out or shape must be accurately alined on the pattern plate without being sprung, before the sand is put in; and after the sand is an'uned' intogplace the drag and cope must beaccu rately assembled by means of a loose closing pin previous to clamping and pouringi 1 e The drag and cope are commonly .providedj on their ends with outwardly projecting lugsbored with round holes to receive removable close-fitting closing pins by whlch the flask members are temporarily held together duringassembling and prior to being clamped; Those same round holes have heretofore been employed to receive .the fixed centering pins on the pattern plates of the molding machine.

Such arrangement has serious disadvantages, which it isthe purpose of my invention to overcome, without radically altering the construction or increasing thecost.

Two such fixed centeringpins were usually employed, one at each end of the pattern plate. The round. boredholes in the lugs have-heretofore.been located to exactly register with the upright. centering pins on the respective pattern plates when the drag and cope were in good condition, but if either became bent or otherwise distorted, even slightly, both pins would not register exactlywith the corresponding holes in the lugs. When that occurred, one cope lug could? be placed on its pattern plate pin, but the holein the lug ontheopposite end of the cope would fail to register with its pin. The pin on the pattern plate and thehole in ,the lug on the cope or the drag might be out ofalignment either longitudinally with respect to the center line of the flaslnor transversely, or both. As previously noted,

but even very slight springing of the flash.

causes defective molding, because the drag or cope, as the case maybe, after having been filled and rammed, returns to its original distorted condition as soon as it is lifted off the centering pins of the pattern plate. A defective casting is almost sure to result, because the sand mold cracks when the flask again changes shape by springing back into its original condition, eventhough, as above i jects-in view which will appear later in the specifications, my invention consists of the device's described and equivalents thereof.

In the drawings, Fig. 1 is a perspective view, partly broken away, of the pattern plate of a molding machine with a drag thereon, employing my improvement;

Fig. Qis a perspective detail of the lug onthe drag and theprojections on the pat tei-11 .pl'ate;1 p a Fig. 3 is a view of a cope-receivingpattern plate equipped'witha pair of'fixed centering pins, one at each end.

Fig. 4a shows the companion or complementary drag-receiving pattern plate having a pin at one end and a pair of spaced projections at the other end in accordance with my improvement.

Fig; 5xis a side View of the lugs and the claimed and the loose closing pin on end of an assembled flash, the machining of the sides of the lug on the drag indicated by dotted lines.

Fig. 6 is a perspective view, partly broken away, of a two-part flask assembled with a loose closing pin according to the method heretofore employed.

In my improvement I employ the usual drag 8 having one or more lugs 1, 1 at each end. Each lug has a hole 2.

At one end of the drag-receiving pattern plate, shown in Fig. 1-, is an upright centering pin I that enters the hole 2 in a lug 1 of the drag when the drag is placed on the plate ready to be filled. But at the other end of the drag pattern plate I dispense with the usual second pin, because that second centering pin, as heretofore used on the drag pattern plate, will not register with the hole in the lug of the drag if there is even a very slight longitudinal displacement of the lug, caused by the drags distortion. In ngy im provement, on the other hand, longitudinal displacement does not affect the accuracy of alignment on the pattern plate, because the parallel sided lug will fit, even though it may have been shifted longitudinally by distortion of the drag.

Instead of the second centering pin I provide two stationary lugs 6, 6 or their equivalents spaced apart as shown in Figs. 2 and l, their inner opposing faces being accurately milled. One of the lugs 1 on the drag 8 has its lateral faces 7 7 correspondingly milled to a close fit between lugs 6, 6.

Hence, when the drag 8 is placed on the pattern plate 5, as in Fig. 1, and one end of the drag secured to the centering pin 4 in the usual manner the other end is fixed as to its correct location laterally, but not longitudinally, by the milled faces 7, 7 and the two lugs 6, 6. I thereby avoid all necessity of springing the drag, in order to mount it on the plate, even though the drag be con siderably out of shape.

After the drag has been filled and rammed on the drag pattern plate, Fig. 1, it is lifted, inverted, and placed on a flat surface, .as shown in Fig. 5.

Meanwhile the cope 9, with its slitted or bifurcated lug 10 at one end, has been placed on the two upright centering pins of the cope pattern plate 5, Fig. 3. Here, as in the case of the drag, the cope, even though distorted, can be alined on the two centering pins P, 4 because the slitted lug 10 secures correct lateral positioning while permitting acertain amount of longitudinal variation.

The closing pin 3 is then fitted into the two holes in the lugs 1, 1 at each end of the drag 8, the free end of the pin projecting upward, as in Fig. 5. The rammed cope is then removed from the cope pattern plate 5 without inverting, and placed on the drag 8. Here again the bifurcated lug 10 positions the cope accurately laterally without binding longitudinally. It fits the closing pins 3, Fig. 5, exactly as well as it fitted the upright platen pins of Fig. 3.

By the means above described I have produced an improvement which, although simple and easily applied to existing flask members and pattern plates, is effective and valuable in foundry practice because it enables the operator to produce rapid and accurate work on a molding machine, even though the drag and cope may have been injured or sprung out of shape. With my improvement it becomes unnecessary to spring the flask parts in order to place them on the pattern plates of the machine, or to spring them during assembling. The loss of castings that heretofore occurred on account of that practice can thereby be eliminated.

' Having thus described my invention, what I claim and desire to secure by Letters Patent is:

1. A flask-member positioning device for a pattern plate comprising an apertured lug on one end of said fiaslr member and a fixed pin therefor on said plate, a pair of pro jections spaced apart on said pattern plate, an apertured lug on the other end of said flask member, the side faces of said lug adapted to fit closely, with respect to transverse dimensions only, between said projections.

2. A flask-member positioning device for a pattern plate comprising an apertured lug on one end of said flask member and a fixed pin therefor onsaid plate, spaced projections on said pattern plate at its other end, an apertured lug on one end of said flaskmember, said lug having two faces 1na chined, said faces adapted to engage the projections on said pattern plate closely with respect to transverse dimensions, but unconfined longitudinally.

. 3. In combination, a" cope having a lug at each end thereof, one lug having a hole, the other lug bifurcated and constituting a guide-way, a cope-pattern plate having an upright centering pin near each end, a drag having a lug at each end thereof, each lug having a hole, one of said lugs having its two lateral sides faced to constitute parallel guide surfaces, 21 drag-pattern platen having an upright centering pin near one end and a pair of spaced guide members near its other end, said guide members faced to form a parallel sided guideway to receive the parallel-faced lug of said drag, and separate closing pins adapted to closely engage the respective holes and to be received in the bifurcation of said lugs.

4. In combination, a platen, a centering pin and a guide pin thereon, a cope having at one end an opening to receive said centering pin to restrain that end. of the cope from movement either laterally or longitudinally, a guideivay at the other end of said cope to receive said guide pin to restrain that end of the cope from movement laterally but not longitudinally, a second platen, a centering pinand a member, including a guideivay on said platen, a drag having at one end. a hole to receive said centering pin to restrain that end of the drag from movement either laterally or longitudinally, a member at the other end of said drag adapted to be received inthe guideivay on said platen, to restrain that end of the drag from movement laterally but not longitudinally, and closing pins.

5. In combination, a cope platen having a pair of centering," pins, a drag platen having one centering; pin and a guideivay, a cope having a hole to receive one of said cope platen centering pins, and having a guide- Way adapted to receive the other cope platen pin, a drag having a hole to receive one of said drag platen centering pins and having a guide member adapted to received in the gnideway of said. drag platen, and 010s ing pins.

6. In combination, a cope-pattern platen having an upright centering pin near each end, a drag-pattern platen having an upright centering pin near one end and a pair 01. spaced guide members near its other end, a cope having a lug at each end thereof, one

ture.

of said lugs having a hole, the other lug bifurcated to constitute a guidevvay, a drag having a lug at each end thereof, each lug having a hole, one of said lugs having sides comprising parallel guide surfaces, and

separate closing pins adapted to be received I in the respective holes and in the bifurcation of said lugs.

7. In combination, a pair of separable fiaslnmembers, lugs on the ends thereof, a lug of one member bifurcated to comprise an interior guideway, a lag of the other member parallel sided to comprise an eX- terior guide, a platen having tWo centering pins for said first mentioned flask-member HOVARD T. DUDLEY. 

